Hi,

the block version of Enumerable#max (or min) always 
returns nil.

---
p ("a"..."f").min {|a,b| a <=> b } # nil
---

or more telling

---
p ("a".."d").min {|b,a| 
  puts "#{b} <=> #{a}"
  b <=> a
}
---
resulting in
---
b <=> a
c <=> a
d <=> a
nil
---


/Christoph